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61.
V Johannssen S Maune JA Werner H Rudert A Ziegler 《Canadian Metallurgical Quarterly》1997,35(4):161-165
This review is a retrospective study of granulosa cell tumours and thecomas encountered in one hospital between 1970 and 1995. There were 16 granulosa cell tumours and 17 thecomas. The size of the granulosa cell tumours varied from 3 to 30 cms in diameter and no correlation was found between size and evidence of invasion. There was also no correlation between either mitotic counts or histological pattern and evidence of invasion. Evidence of oestrogen production was found in 11 of the sixteen granulosa cell tumours (2 with endometrial carcinoma and 9 with endometrial hyperplasia) and in 9 out the seventeen thecomas (2 with endometrial carcinoma and 7 with endometrial hyperplasia). Thecomas are regarded as benign tumours but granulosa cell tumours are characterised by a long natural history with a significant capacity to recur years after an apparent clinical cure. It is therefore important that patients with these tumours are followed up indefinitely. 相似文献
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HT Wen AL Rhoton E de Oliveira 《Canadian Metallurgical Quarterly》1998,42(6):1205-17; discussion 1217-9
OBJECTIVE: We review the anatomic features of the lateral ventricle, the foramen of Monro, the third ventricle, and the choroidal fissure, and we describe the transchoroidal approach to the third ventricle. This approach consists of opening the taenia fornicis of the choroidal fissure in the body of the lateral ventricle and approaching the third ventricle between the two internal cerebral veins. This route allows further posterior enlargement of the foramen of Monro without sacrificing any neural structures. When necessary, the anterior septal vein can be sacrificed. METHODS: Twenty adult cadaveric brains and four adult cadaveric heads were studied, using a magnification ranging from 3 times to 40 times, after perfusion of the arteries and veins with colored latex. RESULTS: The choroidal fissure is a natural cleft between the thalamus and the fornix, and it is identified by following the choroid plexus in the lateral ventricle. The choroid plexus in the body of the lateral ventricle originates from the tela choroidea of the roof of the third ventricle and is apparently attached to the fornix by the taenia fornicis and to the thalamus by the taenia choroidea. The taenia is actually the ependyma that covers the internal wall of the ventricular cavity and the choroid plexus. CONCLUSION: An understanding of the choroidal fissure is fundamental for use of the transchoroidal approach. Unlike transforaminal, subchoroidal, subforniceal, and interforniceal approaches to the third ventricle, which sacrifice some neural or vascular structures, the transchoroidal approach follows a natural route, and certainly it is one of the options to be considered when entry into the third ventricle is required. 相似文献
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EJ van Zoelen RH Kramer HT van Moerkerk JH Veerkamp 《Canadian Metallurgical Quarterly》1998,19(12):487-490
Scatchard plots are widely used for the graphical presentation of receptor-ligand binding data. When a combination of labelled and unlabelled ligand molecules is used in a binding assay, equations for Scatchard plots are readily available if the labelled and unlabelled ligands have similar binding affinities. In this article, Everardus van Zoelen, Roel Kramer, Herman van Moerkerk and Jacques Veerkamp present mathematical equations to obtain the binding characteristics of an unlabelled ligand in a Scatchard plot, which has a dissociation equilibrium constant different from that of the labelled ligand used. 相似文献
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A special program developed by the authors, called Pombe, identifies protein coding regions in the Schizosaccharomyces pombe genome. Linear discriminant analysis was applied to predict 5'-terminal, internal, 3'-terminal exons (coding-exon) and introns. The accuracy of the prediction was tested by cross verifications. The sensitivity, specificity and correlation coefficient for the internal exon prediction were 98.5%, 99.9% and 98.3% respectively at the nucleotide level. Open reading frames were studied and used to predict intron-less genes: 99.0% of such genes were identified with correct stopping sites. The gene structure was determined by dynamic programming and the prediction achieved 97.0% correlation coefficient at the nucleotide level. The program is available at http:(/)/clio.cshl.org/genefinder. 相似文献
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This study reports the use of Nile Blue, an oxazine dye, as a derivatization reagent that fluoresces in the far-red spectral region and is suitable for derivatization with carboxylic-acid-containing analytes. Model carboxylic acid analytes such as benzoic acid, acetic acid, phenylacetic acid and hexanoic acid have been reacted as acid chlorides to form Nile Blue derivatives. The synthesis product of the Nile Blue benzoic acid derivative was confirmed using electrospray-mass spectrometry, infrared spectrometry, 1H and 13C nuclear magnetic resonance, reversed phase liquid chromatography (RP-HPLC), normal phase-thin layer chromatography, and spectral characterization. The synthesized Nile Blue derivatives, separated from reaction by-products with RP-HPLC, all demonstrated an approximately 10-fold drop in molar absorptivity and relative quantum yield. In addition, a 40 nm increase in Stokes shift was observed. A portion of the fluorescence was regained through post-column ionization of the Nile Blue benzoic acid derivative at pH 12. A RP-HPLC limit of detection of 88.25 fmol on column has been reported with conventional fluorescence detection-post-column ionization of the Nile Blue benzoic acid derivative. A limit of detection of 1.99 fmol on column (3.98 x 10(-11) M) has been demonstrated for the Nile Blue benzoic acid derivative with the use of a laboratory-constructed visible diode laser fluorescence detector. 相似文献